Conventionally, a vehicle control apparatus has been known that inhibits automatic stopping of an internal combustion engine when an abnormality occurs in a negative pressure sensor (see, for example, Patent Document 1). A vehicle having such a control apparatus built in includes a brake booster that assists a braking operation of a driver by using negative pressure in a negative pressure chamber, generated depending on rotation of an internal combustion engine. Also, in this vehicle, when a predetermined stopping condition is satisfied, the internal combustion engine automatically stops, and after the automatic stopping, when a predetermined restart condition is satisfied, the internal combustion engine automatically starts.
The control apparatus includes a negative pressure sensor that outputs a signal depending on the negative pressure in the negative pressure chamber, and detects the negative pressure in the negative pressure chamber based on the output signal from the negative pressure sensor. Then, based on a detected result of the negative pressure, the control apparatus determines whether an abnormality occurs in the negative pressure sensor. Specifically, it determines that an abnormality occurs in the negative pressure sensor if a state continues for a predetermined time or longer during which the output signal of the negative pressure sensor is out of a desired normal range. As a result, if determining that an abnormality occurs in the negative pressure sensor, the control apparatus inhibits the automatic stopping of the internal combustion engine, and automatically starts the internal combustion engine.